- Prosthetic group
A prosthetic group is a non-protein (non-
amino acid) component of a conjugated proteinthat is important in the protein's biological activity. [cite web |url=http://www.chem.qmul.ac.uk/iupac/bioinorg/PR.html#24 |title=Glossary of Terms Used in Bioinorganic Chemistry: Prosthetic groups |accessdate=2007-10-30 |last=de Bolster |first=M.W.G. |date=1997 |publisher=International Union of Pure and Applied Chemistry] The prosthetic group may be organic (such as a vitamin, sugar, or lipid) or inorganic(such as a metalion). Prosthetic groups are bound tightly to proteins and may even be attached through a covalent bond. They often play an important role in the function of enzymes. A protein without its prosthetic group is called an apoprotein, while a protein combined with its prosthetic group is called a holoprotein.
Prosthetic groups are a subset of cofactors and differ from
coenzymes in that they bind permanently to the enzyme as opposed to temporarily for coenzymes. [cite web |url=http://www.chem.qmul.ac.uk/iupac/bioinorg/CD.html#34 |title=Glossary of Terms Used in Bioinorganic Chemistry: Cofactors |accessdate=2007-10-30 |last=de Bolster |first=M.W.G. |date=1997 |publisher=International Union of Pure and Applied Chemistry] In enzymes, prosthetic groups are involved in the active sitein some way.
hemegroup in hemoglobinis a prosthetic group. Further examples of organic prosthetic groups are vitamin derivatives: thiamine(vitamin B1), thiamine pyrophosphate, pyridoxal-phosphateand biotin. Since prosthetic groups are often vitamins or made from vitamins, this is one of the reasons why vitamins are required in the human diet. Inorganic prosthetic groups are usually transition metalions such as iron(in hemegroups, for example in cytochrome c oxidaseand hemoglobin), zinc(for example in carbonic anhydrase), magnesium(for example in some kinases), and molybdenum(for example in nitrate reductase).
List of prosthetic groups
* [http://www.bio.mtu.edu/%7Ehlyoungs/BL4010/cofactors.ppt Cofactors PowerPoint lecture]
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prosthetic group — prostetinė grupė statusas T sritis chemija apibrėžtis Kofaktorius, kuris susijungęs su baltymu kovalentiniu ryšiu padaro jį aktyvų. atitikmenys: angl. prosthetic group rus. простетическая группа … Chemijos terminų aiškinamasis žodynas
prosthetic group — Biochem. the nonprotein acid constituent of a conjugate protein, as the heme group of hemoglobin. [1895 1900] * * * … Universalium
prosthetic group — noun Biochemistry a non protein group forming part of or combined with a protein … English new terms dictionary
prosthetic group — /prɒsˌθɛtɪk ˈgrup/ (say pros.thetik groohp) noun a non protein molecule which is combined with a protein, as the haem group in haemoglobin … Australian English dictionary
prosthetic group — Biochem. the nonprotein acid constituent of a conjugate protein, as the heme group of hemoglobin. [1895 1900] … Useful english dictionary
prosthetic group — A non peptide portion of an enzyme (may be organic or inorganic) that is responsible for the specific biological action of the protein; see coenzyme, cofactor … Dictionary of invertebrate zoology
prosthetic group — (pros thet ik) A tightly bound cofactor that remains at the active site of an enzyme during its catalytic activity … Dictionary of microbiology
prosthetic group — A tightly bound non polypeptide structure required for the activity of an enzyme or other protein, eg. the haem of haemoglobin … Dictionary of molecular biology
prosthetic group — a low molecular weight, nonprotein compound that binds with a protein component (apoprotein, specifically apoenzyme) to form a protein (e.g., holoenzyme) with biologic activity … Medical dictionary
Prosthetic — Referring to a prosthesis, an artificial substitute or replacement of a part of the body such as a tooth, eye, a facial bone, the palate, a hip, a knee or another joint, the leg, an arm, etc. A prosthesis is designed for functional or cosmetic… … Medical dictionary